Chapter 26, Problem 1CC

Complete this map, which presents some major concepts from this chapter.

Summary Introduction

To complete: The given map that shows the internal communication and regulation.

Introduction: There are two major ways of internal regulation and communication. These are regulated by hormones (chemical substances) and neuronal communication (electrical signals). Neuronal regulation is carried out by neurons either electrically or by the help of neurotransmitters. Hormonal regulation is carried out by hormones that are usually peptides or steroid molecules.

Answer to Problem 1CC

Pictorial representation: Fig. 1 represents the chart of the internal communication and regulation by hormones in vertebrates.

Fig. 1: Internal communication and regulation.

Explanation of Solution

(a)

Correct answer: Nervous system

The nervous system is the organ system of the body, which conducts nerve impulses in the form of electrical signals that pass along the dendrites to generate an action potential. Hence, the correct answer is nervous system.

(b)

Correct answer: Hormones

Hormones are the chemical substances that are secreted by a special group of cells or tissues called the endocrine glands. They pour their secretions into the bloodstream. The exocrine glands are also found in our bodies, which pour their secretions in a tube or a duct. Hence, the correct answer is hormones.

(c)

Correct answer: Receptors

Receptors are the structures that are mostly made up of proteins whose function, as the name suggests, is that they receive the signals or the chemicals or hormones and thereby transmit or elicit a response in the cell on which they are present. Hence, the correct answer is receptors.

(d)

Correct answer: Inside the target cell

Receptors are present inside or outside the cell. They receive the hormones that are secreted by the endocrine glands. Their functioning is regulated either by the hormone itself or by some other biomolecules. Hence, the correct answer is inside the target cell.

(e)

Correct answer: Endocrine glands

Hormones are the chemical substances or biomolecules that are secreted or formed by the endocrine cells. The chemical substances that are formed by the exocrine glands are called secretions. Secretions are poured into a tube or a duct, whereas the hormones are secreted directly into the bloodstream. Hence, the correct answer is endocrine glands.

(f)

Correct answer: Pituitary gland

The pituitary gland is also called the master gland as it controls the functioning of all the other endocrine glands. However, this gland is also regulated by the hypothalamus, which is a part of the brain. Hence, the correct answer is pituitary gland.

(g)

Correct answer: Adrenal gland

The adrenal gland is also called the suprarenal gland as it is located above the kidneys. It secretes a hormone called adrenaline, which is also called the 3F hormone or the emergency hormone as this provides the support for the response that is needed in emergency conditions like fighting or in fearful conditions. Hence, the correct answer is adrenal gland.